The revolution in the electronics industry which has occurred in the last few decades has, in significant part, been occasioned by the development of the integrated circuit. Because of the development of that item, many new products not previously available have been made available in various markets. These include the consumer-oriented, industrial, and governmental markets.
Not many years ago, devices such as personal computers were certainly not readily available. It has come to be, however, that the residence without a personal computer is the exception rather than the rule.
One type of integrated circuit which is typically used in many electronic devices, such as computers, which is available because of the development of integrated circuits is known as an EPROM. This acronym stands for "erasable programmable read-only memory". Such devices can typically take one of various forms. One typical, and frequently employed, configuration is that known as a DIP. Other such devices can take the configuration of an LCC (leadless chip carrier) or other packages.
DIPs are microcircuit packages with two rows of contacts. Each row extends from one of opposite lateral edges of a main body of the device and generally perpendicular thereto. Each row can vary in the number of leads it includes. Typically, however, between seven and twenty contacts are provided in each row. The spider-like structure formed by the contacts and the main body portion of the device renders the device capable of being easily inserted into a circuit board.
LCCs are microcircuit packages with contacts which do not extend beyond the edges of the device. Such devices are surface-mounted on etched circuit boards.
Since some of the devices described immediately above are erasable and programmable, various types of equipments have been designed to accomplish the programming function. The equipment is provided with one or more master devices, the memory of which is to be dubbed onto various EPROM devices which are passed through the machine. Typically, passage of the devices to be programmed is effected by allowing them to slide, under the influence of gravity, down an inclined track. Multiple stations are defined at various locations along the track so that a plurality of EPROMs can be simultaneously programmed.
When a device to be dubbed is at a desired station, or a plurality of devices are at a corresponding plurality of stations, the signature to be imposed is applied only after first testing the devices for shorts. This is accomplished by driving current through the devices and ascertaining the flow characteristics.
Progamming is, thereafter, completed. This is brought about by applying a defined voltage to various contact pins. before releasing the devices to a station at which they are marked with appropriate indicia, correct programming is verified.
Electronic connectors are made to engage the contact pins of the devices to be programmed in order to effect the driving of current through the device and the application of voltage thereto. Typically, the electronic connectors take the form of "pogo pins". Such pins are biased toward a position in which they engage the contact pins of a device at a station of which a particular pin is a part. They are, however, spring-loaded so that there will be a cushion in order that the contact pins of the devices to be programmed not be damaged.
Various diffferent types of stops have been employed for engaging a device when it is at an appropriate position and in station relative to corresponding "pogo pins". These stops, as known in the prior art, however, tend to be overly intricate and complicated.
Additionally, many of such stops, do not take into account the fragility of the devices which are intended to be programmed. Many EPROMs are made of materials which are brittle, and many devices employed as stops in the prior art have no give when they are contacted by a device passing down the track. Consequently, the possibility to damage to a significant number of the devices to be programmed escalates.
Additionally, the same programming equipment is, it is desired, used to program EPROMs of different dimensions in a direction axial with respect to the track down which they pass. Consequently, the axial position of engagment of the EPROM with its respective stop must be able to be varied depending upon the relative location of the contact pins with respect to the axial dimension of the device. Many devices known in the prior art do not enable such an adjustment.
When the particular EPROMs being programmed are DIPs, additional problems are encountered. The contact pins of such devices are easily deformable, and, often, the engagement of the pins by the "pogo pin" electronic connectors can result in inadvertant bending. This is particularly true should one or more of the "pogo pins" become jammed so that there is no telescoping of the contact portion relative to the rest of the pin.
It is to these problems and dictates of the prior art that the present invention is directed. It is an improved equipment which makes significant strides towards solving the problems of the prior art.